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				<div class="regiontitle">News</div>
				
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				<div class="regiondetail">Recent information on the field</div>
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				<div class="sectiontitle"><span class="warning">WARNING: Staples and Shear Panels Failure</span></div>

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					Staples used to connect shear panels may fail without notice:<br />
					<br />
					Recent tests of shear walls that used structural staples to connect the shear panels showed that the
					staples can fail at the interface between the stud and the shear panel even though the staple crown
					shows no distress on the outside face of the shear panels. This can produce a sudden, unexpected
					failure of the shear wall.<br />
					<br />
					The Structural Engineers Association of California (SEAOC) has suggested limiting the use of stapled
					shear panels. View SEAOC's <a href="http://www.shearwalls.com/resources/seaoc-staple-bulletin.pdf">bulletin</a>
					regarding stapled shear walls for more information.<br />
					<br />
					Hard-core engineers may be interested in structural engineer Ben Schmid's
					<a href="http://www.shearwalls.com/resources/esr-1539-comments.pdf">comments</a> on code approval
					report for staples (this is about a 1 MB file of four scanned pages).
				</div>
			
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				<div id="PRESSURETREATEDWOOD" class="sectiontitle"><span class="warning">WARNING: Pressure-Treated Wood and Fastener Corrosion</span></div>

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				<div class="sectiontext">
					SUMMARY
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				<div class="sectiontitle">The Problem</div>

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					Up until January 1, 2004, the most common chemical used as a preservative for pressure-treated wood was CCA
					(Chromated Copper Arsenate). CCA is no longer allowed as a treatment for wood used as foundation sills (mudsills)
					in residential construction. Some of the new chemicals used for preservatives include ACZA (Ammoniacal Copper Zinc
					Arsenate), CA (Copper Azole), CC (Copper Citrate), ACQ (Ammoniacal Copper Quat). All of the preceding chemicals
					bond with the wood cells, giving a "waterproof" treatment.<br />
					<br />
					ACZA, CA, CC and ACQ are much more corrosive than CCA because they contain more copper. Copper and steel react
					chemically, and the steel corrodes. The building codes require hot-dipped galvanized, stainless steel, silicon-bronze,
					or copper fasteners for connecting treated wood. This would include all fasteners that contact the treated wood, such
					as sill anchors, framing clips, nails used to connect studs or sheathing to the sills, anchor rods for shear wall
					tie-downs, and so forth. The codes go on to say that you can use only steel or stainless steel for structural
					connections (such as shear panel nailing). The major hardware manufacturers (Simpson and USP) recommend STAINLESS
					STEEL fasteners for connecting wood treated with any of the above chemicals. Hot-dipped galvanized fasteners, even
					"triple-dipped," are not adequate!<br />
					<br />
					The following is a quote from a preservative industry document regarding corrosion:<br />
					<br />
					<div class="quote">
						"It is generally recognized that the potential for fastener corrosion in forest products based building materials
						used in an interior exposure environment is minimal because the equilibrium moisture content of the wood is
						maintained at a level that does not	support corrosion reactions."
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					<br />
					Note that foundation sills ("mudsills") are required to be treated wood specifically
					because they will have elevated moisture levels due to moisture wicking up through the concrete from the ground. You
					do not want your project or home to be a trial laboratory for testing fastener corrosion.
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				<div class="sectiontitle">The First Report</div>

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					The following is an excerpt from a letter that appeared in the July, 2009 issue of Journal of Light Construction.
					This is a very grim report on the effects of ACQ lumber on galvanized nails and anchor rods. Other contractors
					have had similar experiences.<br />
					<br />
					<div class="quote">
						<span class="sectionsubheading">"Hardware Corrosion From PT Lumber: Looking for Answers"</span><br />
						<br />
						I've been a professional builder and contractor for 20 years and am glad somebody finally has enough sense to
						develop a less corrosive treatment ("Pressure-Treated Wood: The Next Generation," Journal of Light Construction,
						April, 2009). In 2005, I built my own house on San Juan Island here in Washington State. ACQ lumber had not been
						on the market for long, and I'd already had some experiences with the extreme corrosion it causes. Using lumber
						that corrodes metal made no sense to me...<br />
						<br />
						During the framing of the house, I had to move a door opening; it was in a shear wall and had a big hold-down
						(HD8A) next to it that needed to be moved, so it required engineering approval. I reframed the doorway and
						installed a new epoxy-grouted anchor and hold-down. I cut off the existing anchor rod for the old hold-down - a
						7-8-inch diameter galvanized rod. <b>The anchor rod had been in contact with the ACQ mudsill for about two months
						- it was the rainy spring season, so it had been almost constantly wet - but already it looked like it came from a
						200-year-old shipwreck! There were no threads left where it passed through the mudsill, and I estimated that the
						corrosion had eaten away 20 percent of the diameter.</b> (Per Code, if a bolt is over 1/2-inch in diameter, you don't
						even need galvanizing.)<br />
						<br />
						Recently, after reading your article, I climbed into the crawlspace and pulled some toenails out of a kneewall.
						The 10-penny nails had been driven through untreated 2x6 studs into ACQ-treated mudsills. The nails were hot-dipped
						galvanized, as recommended at the time. What I found was very scary, since the shear strength of a nail is a
						function of the diameter: <b>These nails had maybe 25 percent of their diameter left.</b><br />
						<br />
						Do I have some weird super-corrosive condition going on here, or are all the houses built since 2004 now ticking
						time-bombs? Not only are the studs no longer effectively nailed to the mudsills, but the anchor-bolt shear strength
						is shot, and the plywood nailing into the mudsills along the base of the shear walls is worthless. When The Big One
						hits, all the engineering and effort to strengthen a house for earthquakes is no better than the connection to the
						foundation--which, based on my observations of this house, will be nonexistent in a few more years.<br />
						<br />
						Does anybody have any answers for this? Is anyone in the industry really looking at the ACQ corrosion issue as it
						concerns the multitude of houses, remodels, and decks that have been built using treated lumber since it was forced
						down our throats?<br />
						<br />
						Steve Mittendorf<br />
						<a href="http://www.mittqc.com/">Mittendorf Quality Construction</a><br />
						Seattle<br />
					</div>
					<br />
					For the full text of this letter, see:<br />
					<a href="http://www.jlconline.com/cgi-bin/jlconline.storefront/4a66919c13e51ef527170a32100a0698/UserTemplate/82?s=4a66919c13e51ef527170a32100a0698&c=cabb224ce4537dd56837e7773ba4c062&p=1">HTML</a> Version of Letter<br />
					<a href="http://www.jlconline.com/cgi-local/view.pdf/90774aa45beff9da7c4a56311b1d111d/www.jlconline.com/cgi-bin/jlconline.storefront/4a66919c13e51ef527170a32100a0698">PDF</a> Version of Letter (Note: this file may only be available to JLC Online members)
				</div>
			
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				<div class="sectiontitle">A Better Alternative</div>

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					Another class of treatment chemicals is Borates, such as DOT, or Disodium Octaborate Tetrahydrate.
					Of the current Borate treatments, DOT does not corrode fasteners as much as CCA did, and therefore
					does not require special fasteners. Borates will disolve in water, so borate-treated wood must be
					protected from liquid water. Borate-treated wood is perfectly acceptable for use in foundation sills.
					Borates are not toxic to humans (this is the same class of chemicals as borax that you use to wash
					your clothes or hands, and is a major ingredient in dishwasher detergent). Borates are much less
					harmful to the environment than copper and arsenic-containing wood treatments.<br />
					<br />
					<span class="listtitle">For more information on borates, visit or search for:</span><br />
					<ul class="tightlist">
						<li><a href="http://www.borax.com/borates2g.html">"Timbor"</a> by US Borax</li>
						<li><a href="http://www.archchemicals.com/Fed/WOLW/Products/Preservative/Sillbor/faq.htm">"Sillbor"</a> by Arch Chemicals</li>
						<li><a href="http://www.osmosewood.com/advanceguard/advanceguard-faq.html">"Advance Guard"</a> by Osmose</li>
						<li><a href="http://www.eswoodtreatment.com/">"EnviroSafe Plus"</a> a product to help make DOT more water resistant</li>
					</ul>
					This is more text.
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				<div class="sectiontitle">More Information on Nails</div>

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					Not all "galvanized" fasteners are created equal. Most nail gun manufacturers use galvanized wire to
					make their "galvanized" nails. The heads and points of such nails have no galvanizing. The head is
					the last part of the nail that you want to corrode, yet nails manufactured from galvanized wire have
					the least protection at their heads. If you need nails that will last, you can get collated (gun)
					nails that are hot-dip galvanized after manufacture. One manufacturer of such nails is
					<a href="http://www.mazenails.com/">Maze Nails</a>.<br />
					<br />
					shearwalls.com recommends <b>stainless steel</b> fasteners for contact with lumber treated with anything
					besides borates.
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